As US forces advance on Baghdad, Saddam Hussein continues to issue statements of defiance - while his officials warn the coalition forces that the capital will be their graveyard.

The fight for Baghdad is likely to be long and bloody

So what is the Iraqi leader's strategy as his forces prepare to defend Baghdad?

For days, senior Iraqi officials have offered the American and British forces an ironic welcome to their capital.

It is a message of both defiance and bravado: "Enter Baghdad if you dare - we're waiting for you".

Events in the southern city of Basra have been, in some ways, a dress rehearsal for the battle of Baghdad.

Unexpected strength

In Basra, Saddam Hussein showed he could hold on to a city for longer than his enemies had expected, by using trusted paramilitary forces to terrorise the local population.

The difference, of course, is that Baghdad - together with Tikrit, the town north of the capital that is home to Saddam Hussein's clan - are much more important to him.

There is even speculation that Saddam Hussein might choose to fight his last battle in Tikrit, rather than Baghdad.

Saddam wants war to be long and bloody

But in any case it is already clear he is trying to maintain the tightest possible grip on the capital, a sprawling city of some five million inhabitants.

If he was anxious to prevent an uprising in Basra, he has even more reason to try to prevent an uprising - or a coup - in Baghdad.

He has dispersed Baath Party officials and members of his various militias throughout the city, on every street and every street corner.

In addition, he is relying on what he regards as his most loyal elite force - the 20,000-strong Special Republican Guard - to provide his last line of defence.

Suicide attacks

His officials have promised there will be suicide attacks against the enemy - and US forces are clearly steeling themselves for the possibility the Iraqis will use the chemical weapons which they so staunchly deny possessing.

The Iraqi aim is to entice US forces into the city and then capitalise, in propaganda terms, on the casualties both sides would be likely to suffer.

He may believe there is an outside chance a prolonged and bloody battle for Baghdad would force the big powers to intervene and call a halt.